The invention relates to a beverage dispensing apparatus comprising
a housing having a chamber formed with an opening through which a beverage container can be placed into the chamber, which container has at least one deformable wall portion and has an outlet to which a beverage delivery line to a tapping device can be connected,
a cover for closing the opening of the chamber,
locking and sealing means for closing the chamber in an airtight manner so as to form a pressure space situated between the deformable wall portion of the beverage container and an inner wall of the chamber, and
pressurizing means for pressurizing the pressure space to force beverage out of the container via the outlet.
Such an apparatus is known from WO-A-95/20540 and is intended for dispensing aerated or non-aerated beverages, particularly beer. In this known apparatus a flexible bag containing a beverage is accommodated in a chamber of a vessel, after which the chamber is hermetically sealed by means of a cover. The space between the chamber and the bag is pressurized. A flexible hose connects an outlet of the bag to a beverage delivery tap. To this end, the hose is passed through an opening in the cover. A drawback of this construction is that the hose in this opening should be sealed very effectively because the hose is situated, at least partly, in the pressure space.
It is an object of the invention to improve a beverage dispensing apparatus of the type defined in the opening paragraph, in such a manner that the afore-mentioned drawback is avoided and, in addition, the apparatus becomes user-friendly.
To this end, the beverage dispensing apparatus is characterized in that the locking and sealing means are arranged between the beverage container and the chamber so as to form the pressure space between an inner wall of the chamber and at least the deformable wall portion of the container, the outlet of the container being situated outside the pressure space.
Now the pressure space is no longer bounded by the cover. The line or hose coupled to the outlet is now situated wholly outside the pressure space. The sealing problem as mentioned hereinbefore for the apparatus in accordance with WO-A-95/20540 does not occur any longer. An additional advantage is that owing to the position of the locking and sealing means it is now possible in a simple manner to automatically create a pressure space when the beverage container is introduced into the chamber of the housing. Operation becomes easier for the user.
A preferred embodiment of the apparatus is characterized in that the locking means comprise spring-loaded locking slides which cooperate with a flange of the container to lock the container in the chamber. When a beverage container is introduced into the chamber the outer wall of the container pushes the locking slides back against the force of spring until a flange of the container has moved past the locking slides, after which the locking slides spring back and lock the container.
An embodiment including a variant of the afore-mentioned locking means is characterized in that an edge of the opening of the chamber has been provided with an annular part on which the locking slides are mounted so as to be resiliently movable in radial directions.
A preferred embodiment is characterized in that the apparatus includes an annular collar mounted onto a neck with the outlet opening of the container, the collar having a flange for cooperation with the locking slides to lock the container in the chamber. Such a collar can be fixedly connected to the container or can be constructed as a separate removable part. The sealing means are constituted by sealing rings between the inner wall of the chamber and an outer flange of the collar and, in the case of a separate removable collar, an additional sealing ring between the neck of the container and an inner flange of the collar.
The apparatus further comprises an unlocking mechanism for unlocking the container. Further details of this are given in the description of an embodiment with reference to the Figures.
A further embodiment of the apparatus is characterized in that the pressurizing means include a pump which can be turned on and turned off by means of a switch which can be actuated by means of the cover. The apparatus further has a pressure-relief valve for the pressure space, which valve can be actuated by means of the cover. When the cover is closed the pressure-relief valve is closed and the pump is started. When the cover is opened the pump stops and the pressure-relief valve for the pressure space is opened, after which the beverage container can be removed from the chamber after this container has been unlocked.
For reasons of hygiene the outlet of a new container filled with a beverage is closed by means of a pierceable sealing membrane. For perforating the membrane the container comprises a piercing mechanism which is connected to a beverage delivery hose and which automatically pierces the sealing diaphragm as soon as the pressure space is pressurized for the first time. For this purpose, the apparatus is characterized in that, when a beverage container is disposed in the chamber and locked, there is some distance between the flange of the container and the locking slides, which enables the container to be moved upward over said distance when the pressure space is pressurized and thus to pierce the membrane.
A construction by means of which a sealing membrane can be pierced is known per se from WO-A-95/20540. However, in said construction piercing must be effected by hand.
In yet another preferred embodiment the tapping device comprises two parts, of which a lower part is fixedly connected to the housing and of which an upper part is hingeable relative to the lower part, the beverage delivery line being partly formed by a flexible hose which can be clamped between the upper and the lower part, which upper part has an actuating handle and which lower part has a shut-off mechanism which in conjunction with the actuating handle can open or can pinch off the beverage delivery hose. This results in a mechanism, which is simple to operate by the user, for installing the beverage delivery hose to the location where the beverage is to be tapped. After the beverage delivery hose has been coupled to the lower part the upper part is secured to the lower part, the hose being clamped in place and at the same time being pinched off. When the actuating handle is opened the hose is no longer pinched and the beverage flows out through the hose under the influence of the pressure in the pressure space.
The apparatus further has a number of safety features to preclude the undesired turn-on of the pressure and the undesirable discharge of beverage.
Owing to the constructional measures that have been taken the operation of the apparatus is very user-friendly as well as safe.